Mining-machine bit



June 10 1924.

L. EVERIST MININGMACHINE BIT Filed May. 25 1921 Patented June 10, 1924.

LOUIS E. EVERIST, OF CHICAGO, ILLINOIS.

MINING-MACHINE BIT.

Application filed May 25, 1 911 1. Serial No. 472,418.

To all whom it may concern:

Be it known that I, LoUIs E. EvERIs'r, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Mining-Machine Bits; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

The invention relates to bits for mining machines, the purpose being the provision in Flgure 4.

of a bit which is practically self-sharpening in so far as it maintains a cutting edge, the bit comprising a layer of relatively hard steel and a body of relatively soft steel which wears away faster than the hard layer, the latter maintaining the cutting edge which is essential to the operativeness of the bit.

Uther objects and advantages will be apparent and suggest themselves as the nature of the invention is understood.

While the drawings illustrate an embodiment of the invention, it is to be understood that in adapting the same to meet different conditions and requirements, various changes in the form, proportion and minor details of construction may be resorted to without de arting from the nature of the invention.

eferring to the accompanying drawings forming a part of the specification,

Figure 1 is a side view of a mining bit embodying the invention,

Figure 1*- is an end view thereof,

Figure 2 is a view similar to Figure 1 of a modification,

Figure 2 is an end view of the modification,

Figure 3 is a view similar to Figure 1 of a further modification,

Figure 3 is an end view of Figure 3,

Figure 4 is a side view showing the hardened layer on a broad side of the bit, and

Figure 4 is an end view of the bit shown Corresponding and like parts are referred to in the following description and designated in the several views of the drawings by like reference characters.

The mining bits illustrated in Figures 1 and 3 are similar in construction in that each contains a layer 1 of relatively hard steel embedded in a body 2 of relatively soft steel, the layer 1 in Figure 1 occupying the minor sessing different axis of the bit, whereas the layer 1 of F igure 3 is disposed coincident with the major axis of the bit. ened layer 1 is centrally disposed and in practice the parts of the-body 2 upon opposite sides of the hardened layer 1 wear equally by direct contact thereby maintaining and preserving a cutting edge.

In the form of mining bit illustrated in Figure 2, thehardened layer 1 is disposed at one side of the body 2 but the operation is practically the same since the relatively soft body 2 wears away by direct contact with the work and exposes a sufficient amount of hardened layer 1 to preserve a cutting edge to the bit.

The component parts of the bit may be united in any manner and the metal employed may be such as best adapted to provide a bit to meet the various requirements. The hardened layer may be united to the relatively soft body by any well known process of welding or joining metals posphysical properties whereby to provide a composite bit for mining operations, particularly in the coal industry.

Figure 4 shows a construction in which the hardened layer is applied to the broad side or face of the body 2 This differs from the construction shown in Figure 2 in which .the hardened layer 1 is applied to a narrow side or face of the body 2 What is claimed is:

A self-sharpening mining machine bit, the same comprising a body of relatively soft and tough steel, said body embodyin a shank and a tooth, said tooth being forme at one end of the shank and having its upper and lower surfaces inclining upwardly at different angles and in converging relation, and a layer of hard steel welded to the body and coextensive with the length and breadth thereof, said tooth being the active part of the bit and adapted to have its softer portion wear away more rapidly than the layer of hard steel, whereby the layer of hard steel will project be yond the active edge of r the body at all times, to present a cutting ed e.

In testimony whereof I a x my signature in presence of two witnesses.

Fomms'r M. POWELL, WILLIAM W. Tocxrm.

with the work, 

